Billionaire Bill Gates has promised to develop a COVID-19 vaccine available to poor countries at less than $3 a dose.

The world's richest countries will likely see an end to COVID-19 within 2021. The rest of the world will just have to wait, Gates said.

Gates, joint founder of Microsoft Corp. and the world's second richest individual with a net worth of $113.8 billion, said recently a COVID-19 vaccine will eventually be developed - but by rich countries first. This is because rich or developed countries have the wealth and industrial capability for large-scale production of any new COVID-19 vaccine.

"The innovation pipeline on scaling-up diagnostics on new therapeutics, on vaccines, is actually quite impressive (in rich countries)," Gates said. "And that makes me feel like, for the rich world, we should largely be able to end this thing by the end of 2021 and for the world at large by the end of 2022."

The role rich countries play in stemming the disease means the pandemic won't continue for five more years or until natural, or herd, immunity sets in. A vaccine, and not herd immunity, is important to beating the disease, he said. "This disease, from both the animal data and the phase 1 data, seems to be very vaccine-preventable," Gates said.

Gates in January 2018 founded the Bill & Melinda Gates Medical Research Institute (Gates MRI), a nonprofit biotech organization conducting clinical research to accelerate product development for diseases and disorders disproportionately affecting the world's poorest populations such as malaria, tuberculosis and diarrheal diseases.

On Aug. 7 Gates MRI entered into partnership with the Serum Institute of India, the world's largest vaccine maker, to develop a vaccine that will be available to poorer countries for less than $3 a dose. The partnership will make up to 100 million doses of a COVID-19 vaccine available for rapid distribution to low- and middle-income countries.

Gates said researchers were making good progress developing safe and effective vaccines for COVID-19. But making sure everyone can get these as soon as possible will require tremendous manufacturing capacity and an international distribution network, he said.

Collaboration between Gates-MRI, India's manufacturing sector and Gavi, the Vaccine Alliance's supply chain will help get a new vaccine to more people in poorer countries, Gates said.